Resilient fastener



K. L( JoHNsoN RESILIENTFASTENER l Oct. 27, 1942.

Filed May 16. 1940 `////`////"////////////M f BY s? TORNEY Patented ct. 27, i942 UNITED STATES PATENT- OFFICE Kenneth L. Johnson, Hampton Township, Allegheny County, Pa.

Application May 16, 1940, Serial No. 335,521

This invention relates generally to fasteners and more particularly to fastenings designed to be driven into one member by repeated blows and having a resilient head and arm portion arranged to engage the member to be fastened.

This invention may be conveniently applied for securing railroad' rails, plate and track castings on supporting members such as crossties. Again these fasteners may be used in fabricated wood or metal structures as a substitute for nails, bolts and the like. A resilient fastener is made of a single piece of metal and consists of a shank portion and an integral head portion having a laterally extending armarranged to engage the member to be fas-V tened When the shank is inserted into an anchored member. The resiliency of the fastener is produced bythe lexure of the arm and the head portions of which there are a number of types. The art discloses resilient fasteners made from square bars and strip stock. In the former theoriginal `cross section is employed as the shank sothat they may be shaped and provide resiliency.

There are several types of resilient fasteners made from strip stock. Some of these are formed by doubling the strip back on'itself to produce a .laminated fastener and others are merely formed from a single continuous strip.

`The form of these resilient fasteners with respect to their head and arm portions may be classied as two distinct types. In one type the impact receiving suface of the head is on the opposite side of the stock than the member engaging surface of the arm. In the other types the impact receiving surface of the head is on the same side of the stock as the member en` gaging surface of the arm. The former type includes those fasteners having their head and arm portions formed by merely bending over the stock. The same type may be made by bending the stock to one side of the shank and then back over the shank to the other side to form a head doubled back on its self. The other type includes those fasteners having their head portion formed either in a loop or ,in a twist. Ineach case the impact receiving surface is on the same side of the stock as the member engaging surface. The latter type consisting `of the two distinct head forms is considered as a preferable structure. n

Each of these typesof resilient fasteners may be constructed from strip stock materially wider than it is' thick. If this stock is approximately and the head and leg portionsare forged CSI 4 claims. (ci. :z5-.10) i of an ordinary cut spikey it may be stiiened, to resist the bending caused by the off-center load application of the arm, by forming a rib longitudinally of the shank, which rib extends through the zone of maximum bending. If the'width of the stock is one and one-half times the dimension of an ordinary cut spike, or more, the shank maybe stiffened by bending the side edges toward one another forming a stiffened shank substan-v tially U-shape in cross section.

'I'he laterally extending arm of these resilient fasteners overlies the member which is to be fastened. When used as spikes for resiliently holding railroad rails to crossties the engaging `portion of the arm exerts a static load on the rail flange, which load is derived from the deflection of the arm created when driving the shank portion into the tie. The arm extends laterally and downwardly and the tip first engages the rail flange at a point spaced from the longitudinal axis of the shank. When` the arm defiects as the spike is driven into the ties this initial enof the arm is moved prothe shank in line with/the arm and travels up the surface of the rail flange.

The purpose of these resilient fasteners is to permit the head intermediate the length of' the train, and since the train is in motion these forces produce a traveling wave motion, causing the rails toraise over.

joints.

It is believed that since the propulsion eifort is applied over a shorter area than` the resistive effort this progressive Wave motion causes the track to creep in the direction of the movement train. Braking forces being applied for This iS the same width as the dimension of a shank retarding a train also causes the rails to creep edge for producing an engaging surface on the rail flange which is complementary to that on the fastener.

Other objects and advantages appear in the following description and claims.

In the accompanying drawing a practical embodiment illustrating the Aprinciples of the ine l vention is shown wherein:

Fig. l is a perspective view of a resilient spike having a loop head structure for illustrating this invention.

Fig. 2 is a perspective view of a resilient spike, the head and arm of which are formed by merely bending over the upper portion cf the stock.

' Fig. 3 is a front elevation of a resilient spike having a twisted head.

Fig. 4 is a plan view showing the fasteners applied to a rail with the shank of each fastener disposed diagonally in the square spike hole in the tie plate, parts being broken away.

Fig. 5 is a sectional view of a resilient spike applied to a rail and taken on the line 5 5 of Fig. 4.

Fig. 6 is an inverted perspective of the tip of a resilient fastener arm showing the incisive portions of the engaging surface.

` Fig. 7 is a view similar to that shown in Fig. 6, illustrating a modified form of the incisive portions of the engaging surface.

Fig. 8 is a view similar to Fig. '7 showing another modified form of the incisive portion of the engaging surface.

Fig. 9 is a longitudinal sectional view of another form of incisive portion.

Referring to the drawing the fastener I0 illustrated in Fig. 1 may be made from a strip approximately one and one-half inches wide and three sixteenths o-f an inch thick. A strip this wide could not pass through the square holes provided in a tie plate. Thus the shank portion II is formed by bending the longitudinal edges I2 toward one another, producing a partially enclosed cross sectional shape such as open tubular, U, V or C shape, depending upon the actual width of the strip and the conventional size of the hole through which the shank is to be driven. The edges may be in close proximity or even overlap. Thus the shank portion is stiened to resist bending by shaping the stock into a longitudinal channel. The lower end of the shank is pointed for driving by pinching in the sides as indicated at I3.

This form of shank resists the bending moments at the point where it enters the member into which it is driven or through which it passes. The forces tending to bend the shank are created by the load application which is spaced from the neutral axis of the formed shank.

To form the loop head the edges I2 of the stock at the upper end of the shank gradually flare outwardly to the full stock width as shown at I4. rThe fiat stock then curves smoothly from the upper end of the shank II into the looped head l5. The head is formed helical to permit the arm I to pass down on one side of the shank to the front of the spike. The under surface of the tip Il engages the member to be fastened. The outer portion of this arm is straight and at of the arm as indicated at 32.

and the under or engaging surface is the same as the impact receiving surface IS.

An incisive portion 2D is formed in the bottom edge of the arm tip I and the form of the profile thereof is extended back along the engaging surface'of the arm as indicated at 2 I.

The fastener 22 shown in Fig. 2 is formed from a strip of approximately three quarters of an inch wide and three sixteenths of an inch thick. The straight shank Il is pointed on its lower end at I3 for driving and is stiffened by the formation of the rib 23 longitudinally of the neutral axis of the shank. rIhis rib should extend from the head I5 down along the shank through the zone of maximum bending which occurs adjacent the point of entry of the shank in the member into which it is driven or through which it passes. The bending forces, as mentioned above, are created by the off-center engagement of the load application. This rib preferably tapers from its full depth to the normal surface of the stock at each end thereof as indicated at 2li.

The head I5 of the fastener shown in Fig. 2 is formed by merely bending over the upper portion of the stock to one side. It is preferably formed in a smooth continuous bend to avoid stress concentrations. The strip is then given a slight reverse curve at 25 to form the substantially straight arm It. The under edge of the tip Il of the arm is also provided with the incisive portion 2B, the form of the profile of which is carried back in the under surface of the arm.

The spike 26 shown in Fig. 3 is made from the same stock of strip metal as that disclosed in Fig. 2 and has the same form of shank II with the stiffening rib 23. The head I5 of this fastener is formed by bending the upper portion of the strip over to one side and down in the same manner as that employed in forming the spike 22 of Fig. 2. The depending portion is then twisted toward the shank as indicated at 2 and bent laterally upward so that the arm I6 extends downwardly and outwardly with its neutral axis substantially parallel to the plane of the broad dimension of the shank. The impact engaging surface I8 is thus the same surface of the strip as the member engaging surface of the arm and the lower edge of the tip I1 is provided with the incisive portions 20.

When applied the axes of the arms of the resilient spikes are preferably disposed diagonally to the neutral axes of the rails. As shown in Fig. 4 the spike members 26 are driven through the standard square hole 28 in the tie plate 29 with the broad dimension disposed diagonally with the hole. The arms of the spikes are disposed at an angle substantially forty-five degrees to the axis of the rail 3Q. Left and right hand spikes are provided so that the arms of the spokes on opposite sides of the rail extend in the same general direction. This should be adopted for a track over which the trains pass` in one direction only. If the traffic passes in both directions right hand spikes should be used on both sides of the rail and their arms would be extending in opposite directions. In Fig. 4

the traffic travels from right to left of the figure.4

When the spikes are. driven into position the incisive portions 30 gouge into the upper surfaces of the rail flanges 3|, producing an initial cut therein which is complementary to their eutting proiile. Repeated vertical movement of the rails due to traffic running thereover extends thisv cut in the surface of the flange beyond thevtip Repeated Wave.

motion in the track wears deep grooves in the flange surfaces. Thel angular disposition ofthe spikes together ment between theresilient arms and therail prevents it from creeping.

The standard'cut spikes are ordinarilylraised by this vertical movement of the rails and the i `creeping forces are resisted only by the rail anwith the interlocking engage In Fig. the normal position of the spike is p shown in full lines. The upper dotted lines show the spike as the inciser edge of the tip of the arm I6 engages the flange and the other dotted lines indicate the rail at the peak of the wave motion causing increased deflection ofthe arms. The vertical movement of the rail thus causes the arm to oscillate between the full and dotted line positions indicated.

Figs. 6, '7 and 8 show different characters of incisive portions on the underside of the free end of the arms it. The form shown in Fig. 6 may be milled or ground, whereas the forms shown in Figs. 7 and 8 may be' forged or pressed during the forming operation of the spike.

A plurality of incisor cutting profiles 33 may be formed on the individual ridges as indicated in Fig. 9. If the spacing between aligned incisor profiles 33 is equal to or less than the normal longitudinal movement of the arm I6 relative to the rail then one prole 33 may take up the cutting action of 'the other and thereby increase the gripping action between the rail and the arm. The individual incisor teeth 33 may be formed by backing off the ridge of the teeth and thereby producing an abrupt cutting profile.

It has been generally accepted in the art that a resilient railroad rail fastener be designed to apply a load of a thousand pounds. The interfacial friction created by this load between the fastener and the rail flange may retard creepage of the rail to some degree. The Wave motion produced in the rails by traffic is believed to be an irresistible force which will either flex the"` resilient fasteners or lift the ties from the road bed, or both.

Generally a resilient spike designed to apply a thousand pound load will flex and absorb a portion of the wave motion relative to the tie and the balance of this motion lifts the tie from the road bed. Vertical movement of the ties produces an undesirable condition which is detrii mental to the road bed. In warm climates the oscillating action of the ties disturbs the road bed by pumping moisture to the surface of the road bed. In cold climates the ties will freeze in the road bed and will resist movement, thus requiring the resilient fastener to assume the full magnitude of the wave motion: If the resilient fastener is driven into the tie to a depth at which it applies a load of a thousand pounds to the rail flange and it is required to flex and absorb the full wave motion of the rails itwill be worked beyond its elastic limit, thereby destroying the resilient characteristics and causing failure.

wave motion to avoid To accomplish this end spikes to assume thel full disturbance of the ties.

`the resilient load characteristics of the spikes must be decreased so that the initial holddown pressure isless than one thousand pounds. This may be accomplished in two ways; first, by reducing the load characteristics by designing a lighter spike, andsecondly, by driving an o rdi nary spike designed to produce a thousand pound load under full deflection, to a lesser depth in the tie. Having been applied with the arm under partial deflection the initial load of the spike will be materially less than one thousand pounds. Under these conditions the full magnitude 0f the wave motion will be assumed by the spikes alone; the ties will remain in the road bed unf disturbed; and the ilexure of the spike will be completely within the elastic limit of the material.

The initial load pressure of a resilient spike driven until the arm is partially deflected is sufficient to maintain the interlocking engagement of the contacting surface comprising this invention. The resistance against creepage that may have been obtained with the interfacial frictional engagement of an applied load of one thousand pounds is more than compensated for by the interlocking engagement applied under loads of a fractional part thereof. Again Ythis interlocking engagement prevents rail creepage with the additional advantage of not disturbing the ties in the road bed.

The initial pressure of the resilient spike is suflcient to hold the incisors in their complementary formed surfaces on the top of the rail flanges, which is a positive check against rail creepage, whereas interfacial frictional engagement may merely retard creepage.

The full magnitude of the wave motion is absorbed by the resilient spikes which have a reduced `initial load application. The repeated flexure of the resilient arms of these spikes due to the wave motion in the rails, causes the cutting profiles of the incisor portions to cut to the full However it is desirable to require the resilient depth of the incisors forming the interlocking surfaces. Since these surfaces are disposed at an angle to the creepagefof the rails they resist longitudinal advancement of the rail in the direction of the traffic.

I claim:

1. A resilient railway spike comprising a relatively stiff shank for driving into a tie, an integral lresilient arm arranged to flex intermediate of its free extremity and the shank and having its outer portion normally depending at an acute angle with the shank, and incisive portions on the free end of the resilient arm arranged to engage and cut extended complementary grooves in the top surface of a rail flange.

2. A resilient railway spike comprising a relatively stilf shank for drivinginto a tie, an integral resilient arm arranged to flex intermediate of4 its free extremity and the shank and having its outer portion normally depending at an acute angle with the shank, and incisive portions on the free end of the resilient arm arranged to engage and cut extended complementary grooves in the top surface of a rail flange, said incisive portions being substantially parallel to the longitudinal axis of the arm. i

3. A resilient'l railway spike comprising a relatively stiff shank for driving into a tie, an integral resilient arm arranged to ex intermediate of its free extremity and the shank and having its outer portion normally depending at an acute angle with the shank, and a series of aligned incisive portions on the under face of the free end of the resilient arm arranged to engage and cut extended grooves in the top surface of the rail ange by the driving action of the spike and by the lifting movement of the rail when traffic moves thereover.

4. A resilient railway spike comprising a shank arranged to be secured to a railway tie, a flexible arm integral with the shank, said arm curving 10 downwardly at an acute angle to the shank and contacting the work below the point of maximum flexure, and incisive means having a cutting profile on the contacting surface of the arm arranged to out a complementary form in the surface of the Work when the spike is applied thereto, said incisive means remaining in interengagernent with the cui; form to prevent lateral movement between the spike and the work.

KENNETH L. JOHNSON. 

